Table 3.

Posterior distributions of 50% effective concentrations (EC₅₀) values (median, standard deviation [SD], and 95% credible intervals [CI]) for DMSO and antibiotics (Amp: ampicillin, Gent: gentamicin) estimated using Bayesian hormetic dose-response curves based on in vitro antimicrobial-antibiofilm assays using Streptococcus pneumoniae and Pseudomonas aeruginosa (per species: n = 7 for DMSO alone, n = 5 for DMSO 1% and 2%, n = 3 for variable DMSO, n = 15 for ampicillin/gentamicin alone).

Bacteria sp.	Experiment	Treatment	EC50 values for antimicrobial activity			EC50 values for biofilm inhibition (%)
			Median	SD	95% CI	Median	SD	95% CI
S. pneumoniae	1	DMSO alone	6.474% DMSO	0.797	[4.915, 8.088]	5.904% DMSO	0.815	[4.308, 7.561]
	2	Amp alone (0% DMSO)	0.168 μg/mL Amp	0.015	[0.139, 0.200]	0.258 μg/mL Amp	0.039	[0.183, 0.336]
		Amp + 1% DMSO	0.168 μg/mL Amp	0.03	[0.114, 0.229]	0.246 μg/mL Amp	0.068	[0.112, 0.382]
		Amp + 2% DMSO	0.16 μg/mL Amp	0.03	[0.106, 0.223]	0.235 μg/mL Amp	0.064	[0.110, 0.366]
		Amp + variable DMSO	0.143 μg/mL Amp	0.031	[0.081, 0.206]	0.196 μg/mL Amp	0.087	[0.038, 0.377]
P. aeruginosa	1	DMSO alone	5.226% DMSO	0.442	[4.377, 6.141]	2.907% DMSO	0.785	[1.374, 4.431]
	2	Gent alone (0% DMSO)	1.505 μg/mL Gent	0.121	[1.329, 1.759]	2.032 μg/mL Gent	0.041	[1.953, 2.114]
		Gent + 1% DMSO	1.378 μg/mL Gent	0.134	[1.116, 1.672]	1.943 μg/mL Gent	0.084	[1.752, 2.087]
		Gent + 2% DMSO	1.172 μg/mL Gent	0.047	[1.088, 1.272]	2.179 μg/mL Gent	0.149	[1.960, 2.535]
		Gent + variable DMSO	1.048 μg/mL Gent	0.029	[1.004, 1.118]	1.504 μg/mL Gent	0.154	[1.203, 1.793]